1. Field of the Invention
This invention relates to holders which keep containers stationary for the purpose of removing container lids. In particular, it relates to such holders which themselves are kept stationary by an attachment to a kitchen sink drain opening.
2. Related Art
Foodstuffs and other products are frequently placed in containers made of metal, glass, plastic or related materials, closed by lids which are twisted off or pried off to open the container. At the factory the lids are securely and strongly attached to the containers to seal and protect the stored product against accidental opening during transit en route to distribution points and retail outlets.
After initial detachment from their containers, most lids are designed to be re-attached to the containers by reversing the detachment motions, such as twisting on or pressing on. As the product is used up, many detach and re-attach cycles are performed by the user. However, because of the nature of manufacture, the initial detachment requires application of a large amount of force, exceeding that needed for subsequent detach efforts.
In many applications the user is able to hold the container with one hand and detach its lid with the other hand. But more often, especially when twisting off by hand, increased leverage for the twisting motion is required. Many devices exist to provide such increased leverage. Sometimes, however, increased leverage is not enough, and it must be accompanied by means to keep the container stationary, such as by clamping in a vise or equivalent.
Therefore a patent search was undertaken for container holders with features to keep them stationary. Two U.S. patents were found: U.S. Pat. No. 5,209,142 (1993) to Dickson, and U.S. Pat. No. 5,345,844 (1994) to Marsaw.
Dickson provides a holder wherein the container is clamped between V-blocks fixed to a base and a piston-like slider. The user""s body weight acting on the free end of the slider provides the force to clamp the container, and further to push the far end of the base against a xe2x80x9cstopxe2x80x9d such as the back wall of a kitchen counter. This leaves both hands free to work on the lid of the container. The drawback of Dickson is that the weight and dimensions of the user""s body must be compatible with the kitchen counter geometry to make his device work for a variety of containers.
Marsaw provides a self-contained device for the mechanical twisting off of a container lid. The device has a base which (a) houses an adjustable rotatable clamp to hold the bottom of the container, and (b) carries a vertically and horizontally adjustable clamp to hold the container lid stationary. Rotation (motorized) of the bottom of the container twists the container off the lid. Marsaw does not provide for detachment of other than screw lids, and shows a rather complicated machine which must be made of metal with close tolerances. The device must have a heavy base to fulfil its lid-detaching function.
An object of the instant holder invention is to avoid use of body force for clamping and enable detaching of container lids of all types.
Another object is to make use of a fixed structure available in the home to keep the holder stationary without affecting the normal use of such a structure.
A further object is a holder capable of clamping containers of various sizes and shapes, leaving the user""s hands free to manipulate container lids.
Yet another object is to provide an inexpensive light-weight device which is simple to operate and easy to clean.
To implement the Objects stated above, the instant invention of a Container Holder with Sink Drain Attachment was devised. The basic concept is an essentially vertical structure with its lower extremity fixedly attachable to a sink drain opening as normally found in residential kitchens, and its upper extremity capable of receiving and clamping the container whose lid is to be removed or affixed. The components of the Holder can be made of plastic material formed by the injection molding process, by metal casting, or by machining of various metallic, plastic or organic materials.
The essentially vertical Holder of the invention has a main body with a thin-walled hollow cylindrical base section which extends down into the sink drain opening, and two parallel columns which rise from the base section to support a circular horizontal container positioning surface on which the container of interest is placed. The next paragraphs detail the attachment of the Holder to the sink drain opening and the clamping of the container on the positioning surface.
The upper extremity of the main body base section is a horizontal partial annular plate which is placed concentrically in contact with the top of the circular sink drain opening. The lower portion of the main body base section is parallel to the curved base section of a pivoting lower half, also having a horizontal partial annular plate, which can be swung horizontally toward and away from the main body base section. Thus the two base sections combine to create a variable size pipe-like funnel extending from the combined horizontal partial annular plates into the sink drain opening. The structure to achieve this is now described.
The pivoting lower half has two short shafts rising vertically upward from its horizontal partial annular plate. One of them, the pivot shaft, serves to pivotally attach the pivoting lower half to the main body base section. The other, the cam lever pivot shaft, serves as the pivot for a cam lever which has an eccentric cam surface in contact with a cam surface on the main body.
By rotating the cam lever the eccentric cam surface on the cam lever is moved along the main body cam surface and the pivoting lower half rotates about the pivot shaft. In one extreme position the pipe-like funnel size is a minimum for insertion in the sink drain opening. Then the cam lever is rotated to expand the funnel to fit tightly in the sink drain opening to attach the Holder. The dimensions are selected to provide a large mechanical advantage for the attach motion.
The container placed on the positioning surface is clamped to the Holder by means of two equal and opposite curved clamping jaws integral with slanted bearing surfaces which encase female thread contours. The female thread contours of both clamping jaws ride on a horizontal screw shaft with matching male threads. The shaft is located in a longitudinal groove cut in the positioning surface. The groove cross-section matches the slanted bearing surfaces of the clamping jaws. One jaw and its adjacent half-shaft carry right-hand threads, while the other jaw and half-shaft carry left-hand threads. A central positioning slot restrains longitudinal shaft motion. When the shaft is rotated by an attached crank handle, the clamping jaws symmetrically move farther apart or closer together depending on the direction of shaft rotation. Thus the jaws can be made to converge on the container and clamp it to the Holder. Again, this shaft and screw arrangement provides a large mechanical advantage for the user.
The advantages of the Holder of this invention include:
1. Use of minimum body or manual force by the user for (a) the attachment of the Holder to the sink drain and (b) the clamping of the container to the Holder, both manipulations being accomplished with a large mechanical advantage, in (a) by rotation of the cam lever and in (b) by rotation of the threaded shaft;
2. Ability to accommodate basic cylindrical containers 2 or more inches in height and typically 1 to 5.5 inches in diameter, also with container perimeters of any regular polygonal shape, and a variety of lid designs, such as twistoff, fliptop, and childproof;
3. Normal sink operation with the Holder installed, including easy mitigation of any spills from the container during lid manipulation or otherwise; and
4. Convenient handling characteristics of the Holder which is lightweight, rapidly installed and removed, and easily cleaned.